IBM MT 2645, Hardware Maintenance Manual

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Symptom-to-FRU error messages
Symptom-to-FRU error messages
This chapter describes the Symptom-to-FRU error
messages.
How to use error messages
Use the error codes displayed on the screen to diagnose
failures.
If two or more error codes are displayed, begin the
diagnosis with the first one. Whatever caused the first
error code can cause false error codes to be displayed.
If no error code is displayed, see if the error symptom is
listed in the “Symptom-to-FRU index.”
How to diagnose multiple FRUs
When an adapter or a device has more than one FRU, the
error code could be caused by any of them. Before
replacing multiple FRUs, try removing or exchanging each
FRU, one by one in the specified sequence, to see if the
symptoms change.
Symptom-to-FRU index
The symptom-to-FRU index lists the symptoms and errors
and their possible causes. The most likely cause is listed
first.
Note: Do the FRU replacements or other actions in the
sequence shown in the “FRU/Action in Sequence”
column. If a FRU replacement does not solve the
problem, put the original part back in the computer.
Do not replace a nondefective FRU.
This index can also help you determine, during regular
servicing, what FRUs are likely to need to be replaced
next.
A numeric error code is displayed for each error detected
in POST or system operation. In the displays, X can be
any number.
If no numeric codes is presented, use the narrative
descriptions of symptoms.
If a symptom is not listed, go to “Undetermined problems”
on page 31.
Note
For an IBM device not supported by diagnostic codes
in the ThinkPad notebook computers, see the manual
for that device.
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